In an automobile's catalytic converter,
several reactions occur to reduce the amount
of carbon monoxide, nitrogen monoxide, and
unburned hydrocarbon pollutants that are
released in the exhaust gases. The exhaust
gases pass over a ceramic honeycombed
structure with a large surface area plated with
the catalysts platinum, rhodium, and
palladium before they leave the tail-pipe. In
spite of these safeguards, however, studies
have shown that most of the pollutants
released from a car happen during the first
one to two minutes after the car is started,
and then decrease significantly after that.
Which factor affecting reaction rates is
responsible for this phenomenon?
A presence of a catalyst
B temperature
C concentration of reactants
D surface area